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If, like me, you enjoy soccer you’ll have been excitedly following the World Cup games. You will probably have caught some of the other hoop-la – including the ‘news’ coverage of an octopus that purportedly ‘predicted’ the outcome of games involving the German team. Now, I’ve been bemused by the coverage accorded to this cephalopod ‘psychic’ – does the press really think Paul the octopus can predict the outcome of a soccer game? I’d like to be charitable & think it’s just reporters looking for a ‘feel-good’ story, or misunderstanding the nature of probability…

After all, let’s look at what the octopus is doing. Offered 2 flag-bearing boxes (one with the German flag, one with the opponent’s), each containing a mussel, he chooses one of them. For the 6 matches involving the German team he appeared to select the winner of each game, including the one that saw Germany go home & Spain progress to the final of the world cup. (A rather tedious game, I have to say…)

Gasp! Surely this is due to more than chance? Well, no. If you toss a coin & record whether it comes up heads or tails, over (say) 100 tosses you’ll see ‘runs’ of several heads or several tails. But each time you toss, regardless of what’s gone before, there’s a 1 in 2 chance of coming up heads. And that’s probably what we’re seeing here. Offer Paul the same choices, multiple times, & I’d predict that you’d see similar results – sometimes he’d be right, & sometimes wrong, & sometimes there’d be a run of correct ‘choices’. (But no-one’s going to do that, of course, because they don’t see a story in it.) However, humans are pattern-seeking creatures & we seem predisposed to imbue mere coincidence with far more meaning than it actually has. And given the amount of press coverage given to self-proclaimed psychics of the human variety, perhaps I shouldn’t be too surprised that the octopus, too, has gained his moment of fame.